Every year at every seder table around the world, millions of Jews recite the 10 plagues. Blood. Frogs. Lice. Flies. Livestock disease. Boils. Hail. Locust. Darkness. Death of the firstborn child.

But why were these the 10 plagues? Why did it take that many plagues to change Pharaoh’s mind? And how are we to explain that last, terrible plague?

Mark Leuchter is the director of Jewish studies at Temple University and an expert on the formation of the Bible and the social and intellectual history of ancient Israel. His first question about the plagues is not “why” or “how,” but “if.”

“I don’t believe that the plagues happened as they are written,” he says. “I believe that they are a combination of myth and memory. I do believe that there was a Moses and an Aaron, and whatever they accomplished was preserved in an oral history that was passed down for generations, then written and condensed.”

Why does Leuchter believe this? “There are documents in which the plagues are described, but not all at once and not in that order,” he says. “Here’s another point. Why is this Pharaoh not named? In the Bible, almost every foreign king was given a name. But not this Pharaoh. That, to a historian like me, is a big red flag.”

Leuchter believes that the plagues are a political allegory that is part of Exodus, the Israelites’ “birth of a nation” story. “And it’s a great story that would resonate with its first audience, the ancient Israelites,” he says. “There is suspense and action, heroes and villains, life and death and, ultimately, freedom. It’s the story of how God destroyed Egypt, the mightiest kingdom of its time.”

How the destruction happened is important, Leuchter says. The plagues are specific. “It’s the systematic dismantling of the Egyptian socio-economic system, which was based on agriculture and the Nile,” he explains. “Ancient audiences would understand the agricultural impact of the plagues and their societal ramifications.”

Why are there 10 plagues? “Most ancient people couldn’t read or write,” he says. “I think that whoever standardized the story said, ‘Let’s make it easy to remember. You have 10 fingers. Count ’em off.’ That’s what would happen later with the Ten Commandments.”

“So the story is, ‘Our god brought Pharaoh and Egypt to its knees. That’s why we Israelites have the right to live independently.’ Does it matter if the story is true or not?”

It matters to Rabbi Eli Hirsch of Mekor Habracha and Rabbi Albert Gabbai of Congregation Mikveh Israel, both in Center City. Hirsch and Gabbai believe that Leuchter’s disbelief is almost Pharaohistic. To them, doubting the plagues is doubting the power and purpose of God.

“Having not found proof of the plagues doesn’t mean they didn’t happen,” Gabbai, who lived in Egypt, says. “It means the proof has not yet been found.”

“Are there acts of nature that can account for some of the plagues? Yes,” Gabbai says. “For example, the plague of blood in the Nile. We know that sometimes, the Nile turns red. When I was a child, I saw it with my own eyes. The rain brings the red clay from the mountains of Ethiopia into the Nile. But I would say this: In either case, the hand of God is there.”

But if that hand of God is all-powerful, why did it take 10 plagues to free the slaves? “The point is not for God to prove His power,” Hirsch says. “Observant Jews already believed in God’s power. The audience of the plagues is the recipient of them: Pharaoh. And, to some extent, Moses himself.

“Don’t forget that Moses was raised as an idol-worshipper, and it took him time to understand monotheism, which is why he continually asks God to prove himself through various tricks and miracles,” Hirsch says. “Also, Moses and God argue about how to do the Exodus. Moses wanted God to be Superman and solve all his problems. So, they try it that way first, and it doesn’t work. At that point, God tells Moses that Pharaoh, like Moses himself, will have to go through the problems — the plagues — to get the solution: freeing the slaves and believing in the power of God.”

As for the question of why God didn’t “make” Pharaoh free the Hebrews, Gabbai utters two words: free will. “God gave us — even Pharaoh — free will to make decisions,” he says. “Sometimes that works out well for humans — and sometimes not.”

And, while Hirsch says that God is the embodiment of lovingkindness, he wasn’t quite feeling it for the Egyptians. Ten plagues gave God the opportunity to vent his wrath at Pharaoh and his people.

“There is definitely an element of ‘You’ve hurt my people, with whom I have a long-term, loving relationship, and now I will make you suffer,’ ” Hirsch says. “In fact, the plagues are there to take specific retribution for specific acts against the Jews. Blood in the Nile is because the Egyptians drowned Jewish children in the river. Lice is because Jews had lice from working in the fields and the unsanitary conditions they were forced to live in. It’s not an eye for an eye; it’s a plague for a plague.”

The order in which the plagues happened is also important, the rabbis say. They point to the seventh plague — hail — as a turning point. “That is the first time that God tells Moses what he is going to do before he does it,” Gabbai says. “God allows Moses to predict the plague in the hope that Pharaoh will change his mind.”

Why not inflict all of the plagues at once? Or start with the most forceful plagues? “Remember that Egyptians are God’s creatures, too, and he does not want to hurt them any more than he has to,” Gabbai says. “That is why, in fact, we remove the plagues from our cup of wine during the seder. Wine gladdens the heart. Diminishing the wine is diminishing our happiness. Despite the fact that the Egyptians were our worst enemy, we feel sorry for their loss. We diminish our own happiness because our freedom came at the expense of their suffering.”

And the worst form of suffering was delivered in that final, terrible plague. “To me, the context is that God was teaching Pharaoh the value of human life,” Hirsch says. “Pharaoh did not value the humanity, lives or religion of the Hebrews. They were slaves to him. Things. How did God show Pharaoh that every human life is precious? He took the human life that mattered most to Pharaoh: his son. If that one human life mattered, then so did the life of every Jew. For Pharaoh to appreciate life, he had to experience death.”

Leuchter has a different, historical explanation. “The tenth plague is brutal, isn’t it?” he says. “But in the ancient world, it was not uncommon for people to sacrifice their first-born child to appease the gods. But the God of Israel claiming the first-born of our enemy? It stinks of power, horror and majesty. It’s an act of war. Pharaohs would have understood it as such and known that none of their gods could perform a plague as terrible as that one, and so the slaves were freed.”

Gabbai recognizes that some ancient cultures regarded children as objects of sacrifice. “But that is why the Torah explicitly tells us not to sacrifice a child,” he says. “That is to separate us from other cultures which did things to children. No one should take a child and ‘pass it through fire’ for God. If He told us that, then He himself wouldn’t do it himself unless He had to. That, to me, is the meaning of the plagues. Look at how much God loves us that He would inflict such suffering so that we could be free. And that is why we must tell the story every year of what God did for us when we came forth out of Egypt. And we should cherish that freedom every day of the year — especially during Passover.”